Mainly because of the NC freeroll points system. They know people will be chasing points and trying to get a seat in the 1 million freeroll. What if they having better live streams this year, isn't the chance to get a little live stream final table time, a ring and your face on the wsop homepage for a day worth something?
Don't get me wrong everyone should play at the Beau, and with the better rakes of course it's a better deal, but they don't bring to the table what WSOPC does. Not saying huge fields at Biloxi but look at Chicago last year and tell me the WSOPC Biloxi does not have tons of room to grow?
I'll just say both places are great and have great poker rooms and directors~